The torban has approximately 30 strings
made of gut [6-8 of them stoppable on the fingerboard, and these
often were double], although instruments having up to 60 strings
are reported to have existed [the doubling of stoppable and bass
strings makes this realistic].The Humenyuk book on the Ukrainian
folk instruments (1930) reprint a rather peculiar tuning system
first given by Lysenko in 1892:Trebles/Prystrunky: 12 or 13 single
strings from f up to c/d in the f-major scale.Main strings/Vtory:
4 single fingerboard frettable strings, bottom to top: c, f,
a, c.Basses on the fingerboard, octave strung, bottom to top:
c, d, f, Bb,Basses off the fingerboard, octave strung, bottom
to top: f, a, Bb, REPEATED TWICE, logic unclear, possibly an
error and octave stinging was intended.